Jesse, a faster GPU will make your life a lot easier. As image files get larger, my impatience of waiting for previews to render gets shorter. I'm building a new workstation as soon as I get my office de-cluttered.
As for camera upgrades, a lot of the stuff on the image quality front has begun to plateau a bit. Now I'm looking for faster focusing, better ergonomics, and more steamlined, intuitively arranged camera firmware. I know my f-stops, shutter speeds, color spaces and histograms inside out, but I don't want to play nuts and bolts while making images. Just give me the basics that I need in easy to access buttons and bury the rest. For some people, digging around in sub-sub-menues for just the right settings is, in and of itself, the enjoyment of photography. Not me. I constantly have contrast ratios, sync speeds and such running around in my head, but I don't want any of it to take priority over the moment playing out in front of me. Canon firmware/hardware seems to strike a good balance for me in that department. Sony...not so much.
There's another problem for me in seeing a video rendering of a scene (mirrorless) versus and optical one (DSLR), but that's a whole nuther ball of wax.